Force sensing resistor (fsr) with polyimide substrate, systems, and methods thereof

ABSTRACT

A force sensing resistor (FSR) that is constructed with a first substrate made of polyimide disposed underneath a second substrate that is resistive and flexible. A handheld controller for an electronic system may include the FSR having a first substrate made of polyimide. The FSR may be mounted on a planar surface of a structure within the controller body, such as a structure mounted within a handle of the controller body, and/or a structure that is mounted underneath at least one thumb-operated control that is included on a head of the controller body. The FSR may be configured to measure a resistance value that corresponds to an amount of force applied to an outer surface of the handle and/or an amount of force applied to the at least one thumb-operated control.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional of and claims priority to co-pending and co-owned U.S. patent application Ser. No. 15/984,231, filed May 18, 2018, entitled “FORCE SENSING RESISTOR (FSR) WITH POLYIMIDE SUBSTRATE, SYSTEMS, AND METHODS THEREOF,” which claims priority under 35 U.S.C. § 120 as a continuation-in-part to pending U.S. patent application Ser. No. 15/834,372 filed on 7 Dec. 2017, entitled “ELECTRONIC CONTROLLER WITH FINGER SENSING AND AN ADJUSTABLE HAND RETAINER,” which itself claims priority as a continuation-in-part to U.S. patent application Ser. No. 15/679,521 filed on 17 Aug. 2017, entitled “ELECTRONIC CONTROLLER WITH HAND RETAINER AND FINGER MOTION SENSING,” which itself claims priority as a continuation-in-part to U.S. patent application Ser. No. 29/580,635 filed 11 Oct. 2016, and claims priority to U.S. Provisional Patent Application 62/520,958 filed 16 Jun. 2017.

BACKGROUND OF THE DISCLOSURE

The video game industry has become large and important, and has spawned many innovations in both software and related hardware. Various hand-held video game controllers have been designed, manufactured, and sold, for a variety of game applications. Some of those innovations have applicability outside of the video game industry, such as for controllers of industrial machines, defense systems, robotics, etc. Virtual reality (VR) systems are an application of great contemporary interest and rapid technical advancement, both within and outside of the video game industry. The controllers for VR systems have to perform several different functions, and meet strict (and sometimes competing) design constraints, often while optimizing certain desired characteristics like ease of use, etc.

One example objective of controllers used in VR systems is to mimic natural interactions, such as grasping, throwing, squeezing, etc., as much as possible. Various types of sensors have been utilized in an effort to meet this objective, including, among others, the force sensing resistor (FSR), which uses variable resistance to measure an amount of force applied to the FSR. However, existing controllers with FSRs tend to exhibit fairly crude response curves (e.g., Force vs. Resistance response curves) due to the materials used in their construction, making them useful for little more than a binary (e.g., on/off) switch. This is undesirable in VR systems. In addition, mylar-based FSRs require a header connector that is large and bulky, which means that the FSR consumes a large footprint, is difficult to miniaturize, and cannot be directly soldered to other components. Yet another drawback of using mylar in the construction of an FSR is its inability to tolerate the high temperatures of a reflow oven, which limits the ways in which manufacturing costs can be reduced for mylar-based FSRs. Instead of using mylar for the bottom substrate, it is also known to construct a FSR with a printed circuit board (PCB) as the bottom substrate. However, PCB substrates also exhibit crude (and sometimes non-monotonic) response curves, rendering these types of FSRs unsuitable for VR applications. Hence, there is a need in the art for an improved controller design that may improve VR systems and/or better facilitate user operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a controller according to an example embodiment of the present disclosure, with a hand retainer in an open position.

FIG. 2 depicts the controller of FIG. 1 in a user's open hand, palm up.

FIG. 3 depicts the controller of FIG. 1 in a user's closed hand.

FIG. 4 depicts the controller of FIG. 1 in a user's hand, palm down.

FIG. 5 depicts a pair of controllers according to an example embodiment of the present disclosure, with hand retainers in an open position.

FIG. 6A depicts a front view of right-hand controller according to another example embodiment of the present disclosure.

FIG. 6B depicts a back view of the right-hand controller of FIG. 6A.

FIG. 7A depicts a window for an infrared light sensor, according to an embodiment of the present disclosure.

FIG. 7B depicts a window for an infrared light sensor, according to another embodiment of the present disclosure.

FIG. 8 shows a side view of the right-hand controller of FIG. 6A, with an outer shell that partially wraps the tubular housing of the controller's handle being exploded away to reveal instrumentation on its inner surface.

FIG. 9A depicts a cross section of the right-hand controller of FIG. 6A, with an outer shell that partially wraps the tubular housing of the controller's handle being exploded away.

FIG. 9B depicts the cross section of FIG. 9A, except with the outer shell installed in its normal operational position.

FIG. 10A depicts a front view of right-hand controller according to another example embodiment of the present disclosure, with a partially-closed hand retainer.

FIG. 10B depicts a front view the controller of FIG. 10A, except with the hand retainer fully open.

FIG. 11A depicts a front view of head and handle components of a controller according to an example embodiment of the present disclosure, including a hand retainer anchor that can move peripherally about the head.

FIG. 11B depicts the head and handle components of FIG. 11A except with a faceplate removed from the head to expose a lockable collar portion that may facilitate selective adjustment of the hand retainer anchor peripherally about the head.

FIG. 12A depicts a partially assembled controller according to an alternative embodiment of the present disclosure, with a hand retainer component removed.

FIG. 12B depicts a closer view of a channel feature of the controller of FIG. 12A.

FIG. 12C is a cross-sectional view of the channel depicted in FIG. 12B.

FIG. 13A depicts a force sensing resistor (FSR) according to an example embodiment of the present disclosure.

FIG. 13B depicts a front view of the FSR of FIG. 13A.

FIG. 13C depicts a cross section of the FSR of FIG. 13B, taken along Section A-A, the cross section showing the first substrate made of polyimide.

FIG. 14 depicts various front views of a FSR at progressive stages in an example process of constructing the FSR.

FIG. 15 depicts example layers of a FSR, according to another embodiment of the present disclosure. FIG. 15 is not to scale. Rather, FIG. 15 is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR.

FIG. 16 depicts example layers of a FSR, according to another embodiment of the present disclosure. FIG. 16 is not to scale. Rather, FIG. 16 is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR.

FIG. 17 depicts example layers of a FSR, according to another embodiment of the present disclosure. FIG. 17 is not to scale. Rather, FIG. 17 is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR.

FIG. 18A depicts a front view of a FSR, before a folding step to form the complete FSR, according to another embodiment of the present disclosure.

FIG. 18B depicts a front view of the FSR of FIG. 18A, after the folding step is performed.

FIG. 18C depicts a cross section of the FSR of FIG. 18A, taken along Section B-B.

FIG. 18D depicts example layers of the FSR of FIG. 18A. FIG. 18D is not to scale. Rather, FIG. 18D is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR.

FIG. 19 is a flow diagram of an example process for manufacturing a FSR.

FIG. 20 illustrates an example user interface (UI) that may be used to configure a FSR-based input mechanism of a controller for an electronic system to operate in different pressure modes.

FIG. 21 depicts a Force vs. Time graph illustrating a “Hair Trigger” style of Soft Press for FSR-based input.

FIG. 22 depicts a Force vs. Time graph illustrating a “Hip Fire” style of Soft Press for FSR-based input.

FIG. 23 depicts the controller of FIG. 1 having various sensors disposed within the controller body.

FIG. 24 is a flow diagram of an example process for re-calibrating a FSR of a handheld controller based on touch data provided by a touch sensor.

FIG. 25 is a flow diagram of an example process for ignoring spurious input at a FSR of a handheld controller based on touch data provided by a touch sensor for an adjacent control.

FIG. 26 is a flow diagram of an example process for adjusting a FSR input threshold for a FSR based on a hand size detected by an array of proximity sensors in the handle of the handheld controller.

FIG. 27 is a flow diagram of an example process for activing and deactivating a binding for a control of a handheld controller based on FSR input values.

FIG. 28 is a flow diagram of an example process for using a time-delay to determine whether to ignore FSR input for a first of multiple thresholds.

FIG. 29 illustrates example components of a handheld controller, such as the controller of FIG. 1.

DETAILED DESCRIPTION

Described herein is, among other things, a force sensing resistor (FSR) that is constructed with a first substrate made of polyimide disposed underneath a second substrate that is resistive and flexible. The first substrate has conductive material (e.g., a plurality of interdigitated metal fingers) disposed on its front surface. One or more spacer layers are also interposed between the first substrate and the second substrate so that a center portion of the second substrate is suspended over the first substrate. An actuator is disposed on the second substrate to convey an applied force onto a front surface of the second substrate. When this occurs, the center portion of the second substrate flexes inward toward the first substrate, and some of the resistive material on the back surface of the second substrate comes into contact with some of the conductive material on the front surface of the first substrate. As the applied force increases, the surface area of the conductive material that is contacted by the resistive material increases. Likewise, as the applied force decreases, the surface area of the conductive material that is contacted by the resistive material decreases. This change in surface area contact under variable applied force causes the FSR to act as a variable resistor whose value is controlled by the applied force.

Due at least partly to the polyimide material used for the first substrate, the disclosed FSR exhibits characteristics that make it desirable for use in a controller of a VR system, among other possible end-use applications. For instance, the polyimide substrate allows for selectively soldering the output terminals (or leads) of the FSR directly onto a board (e.g., a PCB) without the use of a bulky header connector, which allows for a FSR with a smaller footprint, as compared to mylar-based FSRs that require a large, bulky header connector. Because polyimide is commonly used as a material of choice for flex circuits, the polyimide substrate of the FSR allows for conveniently connecting the FSR to other flex circuits, which may reduce the cost of manufacturing the disclosed FSR, as compared to the cost of manufacturing conventional FSRs. Polyimide can also withstand high temperatures, such as those of a reflow oven, opening the door to cost-saving manufacturing processes. In addition, polyimide 13 when used as the first substrate of the disclosed FSR—exhibits desirable characteristics, such as less hysteresis and higher repeatability, as compared to conventional FSRs. Overall, the disclosed FSR, having a first substrate made of polyimide, exhibits a Force vs. Resistance response curve that models a true analog input, making the FSR desirable for use in a controller of a VR system.

Also disclosed herein is a controller for an electronic system (e.g., a VR system) that includes the disclosed FSR having a first substrate made of polyimide. The controller may be configured to be held by a hand of a user and may include a controller body. The disclosed FSR can be mounted on a planar surface of a structure within the controller body, such as a structure that is mounted within a handle of the controller body, or a structure that is mounted underneath at least one thumb-operated control that is included on a head of the controller body. The FSR, when implemented in the controller for the electronic system, is configured to measure a resistance value that corresponds to an amount of force applied to an associated portion of the controller (e.g., a force applied to an outer surface of the handle, to at least one thumb-operated control, etc.).

Implementing the FSR in a controller for a VR system allows for expanding the spectrum of natural interaction beyond its current state using conventional controllers. For example, the electronic system and/or the controller can determine, via the FSR, a force with which a user squeezes the handle of the controller, and/or a force with which the user presses a thumb-operated control. Because the disclosed FSR exhibits a desirable response curve, such a controller can translate presses or squeezes of varying force into a varying digitized numerical value that can be used for a video game to control a game mechanic (e.g., to crush a rock, to squeeze a balloon, the toggle through available weapons usable by a game character, etc.). A FSR with desirable response characteristics can replace conventional mechanical switches in order to reduce fatigue of the user and/or to reduce accidental actuation of the controls. For instance, the FSR can act as a switch by detecting when an applied force exceeds a threshold. This threshold adjusted dynamically. For example, the threshold can be adjusted to a lower value in order to reduce hand fatigue during gameplay (e.g., when the user is pressing a control associated with the FSR to shoot a weapon frequently during gameplay). Conversely, the threshold can be adjusted to a higher value in order to reduce the instances of accidental control operation, which may be useful in a thrilling or exciting game where the user might react to stimuli in the video game.

Also disclosed herein is a handheld controller that includes logic to implement sensor fusion algorithms based on force data provided by a FSR of the controller in combination with touch data or proximity data provided by a touch sensor or an array of proximity sensors, respectively. An example sensor fusion algorithm can be used to re-calibrate the FSR when an object contacts control associated with the FSR, as detected by the touch sensor. For instance, the logic may determine, based on touch data provided by the touch sensor, that an object has come into contact with a control on the controller body that is configured to be pressed. The logic may also determine, based on force data provided by the FSR at a time at which the object has come into contact with the control, a resistance value measured by the FSR, and may correlate the resistance value with a digitized FSR input value of zero in order to “re-calibrate” the FSR upon detecting a touch at the control.

Another example sensor fusion algorithm can be used to ignore spurious inputs detected by the FSR when an object is in contact with an adjacent control. For instance, the logic may determine, based on force data provided by the FSR, a resistance value measured by the FSR that corresponds to a digitized FSR input value which meets or exceeds a threshold value that is to be met in order to register a FSR input event for a first control of the handheld controller. The logic may also determine, based on touch data provided by the touch sensor at a time at which the FSR resistance value is measured by the FSR, that the object is in contact with a second control of the handheld controller that is adjacent to the first control, and may refrain from registering the FSR input event while the object is in contact with the second control.

Another example sensor fusion algorithm can be used to detect a hand size of a hand grasping a handle of the controller, as detected by the array of proximity sensors, and to adjust the threshold force to register a FSR input event at the FSR according to the hand size. This may be useful for making force-based input easier for users with smaller hands (and harder, but not difficult, for users with larger hands). For instance, an array of proximity sensors that are spatially distributed on a handle of the handheld controller can be used to determine a size of a hand that is grasping the handle, and the logic may adjust, based on the size of the hand, a threshold value to an adjusted threshold value that is to be met in order to register a FSR input event for the handle.

FIGS. 1-4 depict a controller 100 for an electronic system according to an example embodiment of the present disclosure. The controller 100 may be utilized by an electronic system such as a VR video gaming system, a robot, weapon, or medical device. The controller 100 may include a controller body 110 having a handle 112, and a hand retainer 120 to retain the controller 100 in the hand of a user (e.g. the user's left hand). The handle 112 comprises a tubular housing that may optionally be substantially cylindrical. In this context, a substantially cylindrical shape need not have constant diameter, or a perfectly circular cross-section.

In the embodiment of FIGS. 1-4, the controller body 110 may include a head (between the handle 112 and a distal end 111), which may optionally include one or more thumb-operated controls 114, 115, 116. For example, a tilting button, or any other button, knob, wheel, joystick, or trackball may be considered as a thumb-operated control if it may be conveniently manipulated by a user's thumb during normal operation while the controller 100 is held in the hand of the user.

The controller 100 preferably includes a tracking member 130 that is fixed to the controller body 110, and optionally includes two noses 132, 134, each protruding from a corresponding one of two opposing distal ends of the tracking member 130. In the embodiment of FIGS. 1-4, the tracking member 130 is preferably but not necessarily a tracking arc having an arcuate shape. The tracking member 130 includes a plurality of tracking transducers disposed therein, preferably with at least one tracking transducer disposed in each protruding nose 132, 134. Additional tracking transducers may be disposed also in the controller body 110, with preferably at least one distal tracking transducer disposed adjacent the distal end 111.

The foregoing tracking transducers may be tracking sensors that are responsive to electromagnetic radiation (e.g. infrared light) emitted by the electronic system, or they may alternatively be tracking beacons that emit electromagnetic radiation (e.g. infrared light) that is received by the electronic system. For example, the electronic system may be a VR gaming system that widely broadcasts, i.e. paints, pulsed infrared light towards the controller 100, with the plurality of tracking transducers of the tracking member 130 being infrared light sensors that may receive or be shadowed from the broadcast pulsed infrared light. The tracking transducers in each nose 132, 134 (e.g. 3 sensors in each nose) preferably overhang the user's hand on each distal end of the tracking member 130, and so are better exposed (around the user's hand) to receive electromagnetic radiation emitted by the electronic system or to transmit the electromagnetic radiation to the electronic system, at more angles without an unacceptable amount of shadowing.

Preferably, the tracking member 130 and the controller body 110 are made of a substantially rigid material such as hard plastic, and are firmly fixed together so that they do not appreciably translate or rotate relative to each other. In this way, the tracking of the translation and rotation of the constellation of tracking transducers in space, is preferably not complicated by motion of the tracking transducers relative to each other. For example, as shown in FIGS. 1-4, the tracking member 130 may be fixed to the controller body 110 by being joined to the controller body 110 at two locations. The hand retainer 120 may be attached to the controller 100 (either the controller body 110 or the tracking member 130) adjacent those two locations, to bias the user's palm against the outside surface of the handle 112 between the two locations.

In certain embodiments, the tracking member 130 and the controller body 110 may comprise an integral monolithic component having material continuity, rather than being assembled together. For example, the tracking member 130 and the controller body 110 may be molded together by a single injection-molding process step, resulting in one integral hard plastic component that comprises both the tracking member 130 and the controller body 110. Alternatively, the tracking member 130 and the controller body 110 may be initially fabricated separately, and then later assembled together. Either way, the tracking member 130 may be considered as fixed to the controller body 110.

The hand retainer 120 is shown in the open position in FIG. 1. The hand retainer 120 may optionally be biased in the open position by a curved resilient member 122, to facilitate the insertion of the user's left hand between the hand retainer 120 and the controller body 110 when the user is grasping for the controller with vision blocked by VR goggles. For example, the curved resilient member 122 may optionally be a flexible metal strip that elastically bends, or may comprise an alternative plastic material such as nylon that may bend substantially elastically. The curved resilient member 122 may optionally be partially or completely internal to or covered by a cushion or fabric material 124 (e.g. a neoprene sheath), for the user's comfort. Alternatively, the cushion or fabric material 124 may be disposed on (e.g. adhered to) only the side of the curved resilient member 122 that faces the user's hand.

The hand retainer 120 optionally may be adjustable in length, for example by including a draw cord 126 that is cinched by a spring-biased chock 128. The draw cord 126 may optionally have an excess length that may be used as a lanyard. The sheath 124 optionally may be attached to the draw cord. In certain embodiments, the curved resilient member 122 may be preloaded by the tension of the cinched draw cord 126. In such embodiments, the tension that the curved resilient member 122 imparts to the hand retainer 120 (to bias it in the open position) causes the hand retainer to automatically open when the draw cord 126 is un-cinched. This disclosure also contemplates alternative conventional ways to adjust the length of a hand retainer 120, such as a cleat, an elastic band (that temporarily stretches when the hand is inserted, so that it applies elastic tension to press against the back of the hand), a hook & loop strap attachment that allows length adjustment, etc.

The hand retainer 120 may be disposed between the handle 112 and the tracking member 130, and be configured to contact the back of the user's hand. FIG. 2 shows the controller 100 during operation with the user's left hand inserted therein but not grasping the controller body 110. In FIG. 2, the hand retainer 120 is closed and tightened over the hand, to physically bias the user's palm against the outside surface of the handle 112. In that way, the hand retainer 120, when closed, may retain the controller 100 to the hand even when the hand is not grasping the controller body 110. FIGS. 3 and 4 depict the controller 100 during operation when the hand retainer 120 is closed, and the hand is grasping the controller body 110 and the thumb is operating one or more of the thumb-operated controls (e.g. track pad 116).

The handle 112 of the controller body 110 preferably includes an array of proximity sensors that are spatially distributed partially or completely around its outer surface. The proximity sensors of the array are not necessarily of equal size and do not necessarily have equal spacing between them, although the array may comprise a grid. The array of proximity sensors is preferably responsive to the proximity of the user's fingers to the outside surface of the handle 112. For example, the array of proximity sensors may be a plurality of capacitive sensors embedded under the outer surface of the handle 112, with that outer surface comprising an electrically insulative material. The capacitance between such an array of capacitive sensors and a portion of the user's hand is inversely related to the distance there between. The capacitance may be sensed by connecting an RC oscillator circuit to an element of the capacitance sensor array, and noting that the time constant of the circuit (and therefore the period and frequency of oscillation) will vary with the capacitance. In this way, the circuit may detect a release of a user's fingers from the outer surface of the handle 112.

When the hand retainer 120 (e.g. a hand-retention strap) is closed tightly, it may serve not only to prevent the controller 100 from falling out of hand, but also to keep fingers from excessively translating relative to the proximity sensor array of the handle 112, to more reliably sense finger motion. The electronic system may include an algorithm embodying anatomically-possible motions of fingers, to better use the sensing from the proximity sensor array to render the opening of a controlled character's hand, finger pointing, or other motions of fingers relative to controller or relative to each other. In this way, the user's movement of the controller 100 and/or fingers may help control a VR gaming system, defense system, medical system, industrial robot or machine, or another device. In VR system applications (e.g. for gaming, training, etc.), the system may render a throwing motion based on the movement of the tracking transducers, and may render the release of a thrown object based on the sensed release of the user's fingers from the outer surface of the handle of the controller.

Hence, the function of the hand retainer 120 (to allow the user to “let go” of the controller 100 without the controller 100 actually separating from the hand or being thrown or dropped to the floor) may enable additional functionality of the controlled electronic system. For example, if the release and restoration of the user's grasp of the handle 112 of the controller body 110 is sensed, then such release or grasping may be incorporated into the game to display (e.g. in VR) throwing or grasping objects. The hand retainer 120 may allow such a function to be accomplished repeatedly and safely. For example, the location of the hand retainer 120 in the embodiment of FIGS. 1-4 may help the tracking member 130 to protect back of user's hand from impacts in real world, for example when the user moves in response to a prompt sensed in the VR environment (e.g. while practically blinded by VR goggles).

In certain embodiments, the controller 100 may include a rechargeable battery disposed within the controller body 110, and the hand retainer 120 (e.g. hand retention strap) may include an electrically-conductive charging wire that is electrically coupled to the rechargeable battery. The controller 100 preferably also includes a radio frequency (RF) transmitter for communication with the rest of the electronic system. Such RF transmitter may be powered by the rechargeable battery and may be responsive to the thumb-operated controls 114, 115, 116, the proximity sensors in the handle 112 of the controller body 110, and/or tracking sensors in the tracking member 130.

As shown in FIG. 5, in certain embodiments the controller 100 may be the left controller in a pair of controllers that includes a similar right controller 200. In certain embodiments, the controllers 100 and 200 may (together) track the motion and grip of both of a user's hands, simultaneously, for example to enhance a VR experience.

FIG. 6A depicts a front view of right-hand controller 600 according to another example embodiment of the present disclosure. FIG. 6B depicts a back view of the right-hand controller 600. The controller 600 has a controller body comprising a head 610 and a handle 612. In the embodiment of FIGS. 6A-6B, the head 610 includes at least one thumb-operated control A, B, 608, and may also include a control configured to be operated by the index finger (e.g. trigger 609). The handle 612 comprises a tubular housing that is partially wrapped by an outer shell 640.

In the embodiment of FIGS. 6A-6B, a tracking member 630 is fixed to the controller body at the head 610 and at an end of the handle 612. A hand retainer 620 is configured to physically bias the user's palm against the outer shell 640 between the head 610 and the end of the handle 612. The hand retainer 620 is preferably disposed between the handle 612 and the tracking member 630, and may comprise a hand retention strap that is adjustable in length and configured to contact the back of the user's hand. In the embodiment of FIGS. 6A-6B, the hand retainer 620 optionally includes a draw cord 628, and optionally can be adjusted in length by a cord lock 626 (adjacent a distal end of the handle 612) that selectively prevents sliding motion by the draw cord 628 at the location of the cord lock 626.

In the embodiment of FIGS. 6A-6B, tracking transducers 632, 633 are disposed on the tracking member 630, with tracking transducers 633 being disposed on protruding noses at opposing distal ends of the tracking member 630. Additional tracking transducers 634 are optionally disposed on a distal region of the head 610. The tracking transducers 632, 633, and 634 may be tracking sensors that are responsive to electromagnetic radiation (e.g. infrared light) emitted by the electronic system (e.g. virtual reality gaming system), or may be tracking beacons that emit electromagnetic radiation (e.g. infrared light) that is received by the electronic system. For example, the electronic system may be a VR gaming system that widely broadcasts, i.e. paints, pulsed infrared light towards the controller 600, with the tracking transducers 632, 633, and 634 being infrared light sensors that may receive the broadcast pulsed infrared light. The response of such tracking sensors may be communicated back to the electronic system, and the system may interpret such response to effectively track the location and orientation of the controller 600.

One or more of the tracking transducers 632, 633, 634 optionally may be structured as shown in the embodiment of FIG. 7A, or alternatively shown in the embodiment of FIG. 7B, or alternatively in a conventional way that is not shown. The lower portion of FIG. 7A depicts an exploded perspective view of an infrared light sensor 750 that is electrically connected to a flex circuit 751, shown beneath a rectangular portion of an overlying windowed housing wall 755 that comprises an infrared-opaque plastic. The windowed housing wall 755 includes a window 756. The window 756 preferably comprises an infrared-transmissive polycarbonate plastic, and may include an underside recession to accommodate the thickness of the infrared light sensor 750.

According to the embodiment of FIG. 7A, the windowed housing wall (e.g. the outer structure of the tracking member 630, or the head 610 of FIG. 6A) may be fabricated from a so-called “double shot” injection molding process, so that the majority of the housing wall is fabricated from infrared-opaque plastic, but with infrared-transmissive plastic being disposed in the window 756 above the infrared light sensor 750.

The upper portion of FIG. 7A depicts a cross-sectional view of the infrared light sensor 750, flex circuit 751, and the windowed housing wall 755 as assembled. Infrared light, shown in FIG. 7A as three downward arrows incident upon the window 756 from above, passes through the window 756 to be received by the underlying infrared light sensor 750. Since the housing wall 755 comprises infrared-opaque plastic, the infrared light that strikes it will not pass through, and a portion may be reflected back into the window to be received by the infrared light sensor 750. In this way, the window 756 permits infrared light to affect the infrared light sensor 750, despite the majority of the housing wall 755 comprising infrared-opaque plastic, so that the infrared light sensor 750 receives infrared light only from a preferred angular range.

Alternatively, one or more of the tracking transducers 632, 633, 634 optionally may be structured as shown in the embodiment of FIG. 7B. The lower portion of FIG. 7B depicts an exploded perspective view of the infrared light sensor 750 as electrically connected to the flex circuit 751, shown beneath a rectangular portion of an overlying housing wall 758 that comprises an IR-transmissive plastic. The housing wall 758 is coated with an infrared-opaque film 757 that is patterned to include a window 759 (where the infrared-opaque film 757 is absent).

The upper portion of FIG. 7B depicts a cross-sectional view of the infrared light sensor 750, flex circuit 751, the housing wall 758, and the IR-opaque film 757, as assembled. Infrared light, shown in FIG. 7B as three downward arrows incident upon the housing wall 758 from above, passes through the window 759 in the infrared-opaque film 757 to pass through the housing wall 758 there to be received by the underlying infrared light sensor 750. Since the housing wall 758 comprises infrared-transmissive plastic, the infrared light that strikes it may pass into it and be lost, and perhaps unintentionally and undesirably even reach a nearby sensor via internal reflections. In this way, the window 759 in the infrared-opaque film 757 permits infrared light to primarily affect the infrared light sensor 750.

FIG. 8 shows a side view of the right-hand controller 600, with the outer shell 640, which partially wraps the tubular housing of the handle 612 being exploded away to reveal instrumentation on its inner surface. In the embodiment of FIG. 8, the instrumentation may comprise an array of proximity sensors 800 that are spatially distributed on the inner surface of the outer shell 640, the array of proximity sensors 800 being responsive to a proximity of the user's fingers to the outer shell 640. The proximity sensors 800 of the array are not necessarily of equal size, nor are they necessarily spaced regularly or equally from each other. In certain embodiments, the array of proximity sensors 800 preferably may be a plurality of capacitive sensors that may be connected to a flex circuit that is bonded to the inner surface of the outer shell 640. In the embodiment of FIG. 8, the outer shell 640 includes a first electrical connector portion 805, which may be connected to a mating second electrical connector portion of the handle 612 (as shown in more detail in FIGS. 9A-9B).

FIGS. 9A-B depicts cross sections of the right-hand controller 600 of FIG. 6A, showing that the controller's handle optionally may comprise a tubular housing 612 a, 612 b, that is split longitudinally by a seam 613 where the tubular housing portions 612 a and 612 b adjoin. In FIG. 9A, the outer shell 640 is shown exploded away from the rest of the handle. FIG. 9B depicts the cross section of FIG. 9A, except with the outer shell 640 installed in its normal operational position. In the embodiment of FIGS. 9A-9B, the first electrical connector portion 805 of the outer shell 640 is shown to be mating and connectable to the second electrical connector portion 905 of the controller handle.

In the embodiment of FIGS. 9A-9B, the outer shell 640 partially wraps the tubular housing 612 a, 612 b in such a way that it preferably overlaps the longitudinal seam 613, so that the longitudinal seam 613 may be positioned to optimize the process of manufacture rather than to accommodate the desired circumferential location of the proximity sensor array 800. In certain embodiments, the outer shell 640 overlaps a circumferential portion C of the tubular housing 612 a, 612 b of the handle, and the circumferential portion C angularly spans at least 100 degrees but not more than 170 degrees of the full circumference of the tubular housing 612 a, 612 b of the handle. Such a circumferential overlap may, in certain embodiments, enable the proximity sensor array 800 to sense the proximity of a desired portion of the user's fingers or palm, for example the region of the hand that best indicates grasping.

The tubular housing 612 a, 612 b of the handle need not have a circular cross-section, and that the word “circumference” is used herein whether or not the tubular housing 612 a, 612 b of the handle has a circular cross-section. Herein, the term “circumference” implies the complete perimeter about the tubular housing 612 a, 612 b of the handle, which may be circular if the tubular housing 612 a, 612 b is a right circular hollow cylinder, but which may be a closed shape other than a circle if the tubular housing is shaped as a non-circular cylinder or hollow prism.

In the embodiment of FIGS. 9A-9B, a printed circuit board (PCB) 920 may be mounted within the tubular housing 612 a, 612 b of the handle, with the second electrical connector portion 905 being electrically coupled to the PCB 920. The PCB 920 optionally includes a force sensing resistor (FSR) 922, and the controller may further comprise a plunger 924 that conveys a compressive force applied via the outer shell 640 towards the outside of the tubular housing 612 a, 612 b of the handle inward to the FSR 922. In certain embodiments, the FSR 922, in conjunction with the proximity sensor array 800, may facilitate sensing of both the onset of grasping by the user, and the relative strength of such grasping by the user, which may be facilitate certain gameplay features.

In certain embodiments, the outer shell 640 has a shell thickness (measured radially in FIGS. 9A-9B) that is less than one-third of a housing wall thickness of the tubular housing portions 612 a or 612 b of the handle. In those embodiments, such a thickness inequality may improve the sensitivity of the proximity sensor array 800 relative to an alternative embodiment where the proximity sensor array 800 is disposed on or in the tubular housing 612 a, 612 b of the handle.

FIG. 10A depicts a front view of right-hand controller 200 according to another example embodiment of the present disclosure, with a partially-closed hand retainer 220 (e.g. a hand retention strap). FIG. 10B depicts a front view the controller 200, except with the hand retainer 220 fully open. In the embodiment of FIGS. 10A-10B, the controller 200 includes a controller body having a head 210 and a handle 212. The head 210 adjoins the handle 212 at a neck region 211 of the controller 200. The handle 212 preferably includes an array of proximity sensors that are spatially distributed just under its outside surface, and that are preferably responsive to a proximity of the user's fingers to the outer surface of the handle 212.

In the embodiment of FIGS. 10A-10B, the head 210 includes thumb-operated controls A, B, and 208. The controller 200 also includes a tracking member 230 that is preferably fixed to the controller body at the head 210 and at a distal end of the handle 212. The tracking member 230 preferably includes a plurality of tracking transducers that may be sensors that are responsive to electromagnetic radiation emitted by the electronic system (e.g. pulsed infrared light emitted by a virtual reality gaming system), or tracking beacons that emit electromagnetic radiation to be received by the electronic system. In the embodiment of FIGS. 10A-10B, the tracking member 230 is preferably but not necessarily a tracking arc having an arcuate shape. The hand retainer 220 is preferably disposed between the handle 212 and the tracking arc 230.

In the embodiment of FIGS. 10A-10B, the controller 200 includes a draw cord 228, and a cord lock 226 adjacent a distal end of the handle 212. The cord lock 226 may selectively prevent sliding motion by the draw cord 228 at the cord lock 226. In the embodiment of FIG. 10A, as the draw cord 228 is pulled progressively further past the cord lock 226, the hand retainer 220 is drawn tighter into a closed position (as shown by the motion arrow depicted in FIG. 10A). The closed position physically biases the user's palm against an outer surface of the handle 212.

In the embodiment of FIGS. 10A-10B, the hand retainer 220 preferably includes a resilient member (e.g. an internal or external elastically deformable strip such as a metal strip) that biases the hand retainer 220 towards the open position shown in FIG. 10B. In the embodiment of FIG. 10B, when the user selectively causes the cord lock 226 to release and permit relative sliding of the draw cord 228, the preloaded bias towards straightening of the elastically deformed resilient member causes the hand retainer 220 to naturally open (as shown by the motion arrow depicted in FIG. 10B). The open position may facilitate inserting or withdrawing the user's hand from the controller 200, especially when the user's vision may be obstructed by the wearing of virtual reality goggles.

FIG. 11A depicts a front view of the head 210 and handle 212 components of the controller 200, including a hand retainer anchor 302 that can be adjusted to move peripherally about the head 210. FIG. 11B depicts the same head 210 and handle 212 components, except with a faceplate removed from the head 210 to expose a lockable collar portion 311 that may facilitate selective adjustment of the hand retainer anchor 302 peripherally about the head 210.

In the embodiment of FIG. 11B, the lockable collar portion 311 may translate along an arcuate path defined by an internal arcuate guide 315. The lockable collar portion 311 can be selectively locked by the user to prevent further movement of the anchor 302 about the periphery of the head 210. Now referring to FIGS. 4 and 10A-11B, the resilient member of the hand retainer 220 is attached to the hand retainer anchor 302 of the head 210, which permits the hand retainer 220 to be adjusted towards or away from the user's purlicue (between the user's thumb and fingers). In certain embodiments, the resilient member of the hand retainer 220 is preferably attached to the hand retainer anchor 302 of the head 210 by a pivoting or rotatable attachment, so that the hand retainer 220 can pivot relative to the hand retainer anchor 302 at the location of the attachment. Such degree of freedom is additional to the adjustability of the position of the hand retainer anchor 302 about the periphery of the head 210.

FIGS. 12A, 12B, and 12C depict an alternative embodiment of a partially assembled controller 400 having a controller body that includes a head 410 and a handle 412 joined to the head in a neck region 411. In the alternative embodiment of FIGS. 12A-12C, the controller body includes a channel 414 that is disposed adjacent the neck region 411. A hand retainer, which is not shown in FIG. 12A so that the channel 414 will not be partially obscured, includes a resilient member 420 that terminates in a projection 425 that extends into the channel 414.

In the embodiment of FIGS. 12B and 12C, the projection 425 includes a catch 427 that prevents longitudinal movement of the projection within the channel 414 when the hand retainer is in the closed position. For example, in the embodiment of FIG. 12C, the catch 427 is a cam that increases friction with an interior surface of the channel 414, when a relative angle of the hand retainer projection 425 corresponds to the closed position of the hand retainer—i.e., when the closed position of the hand retainer results in tension upon the resilient member 420 (e.g. in a downward direction as shown in the cross-section of FIG. 12C).

By contrast, when the hand retainer projection 425 is rotated to a relative angle that corresponds to an open position of the hand retainer (e.g. in an upward direction as shown in the cross-section of FIG. 12C), the friction between the catch 427 and the channel 414 is reduced, and the hand retainer projection 425 may be translated within the channel 414 (as indicated by the motion arrows shown in FIG. 12B). The channel 414 is preferably oriented so that translation of the hand retainer projection along the channel 414 preferably adjusts the relative position of the hand retainer projection 425 towards or away from the purlicue of the user's hand, for example so that the controller 400 can accommodate different hand sizes or finger lengths. In an alternative embodiment, the hand retainer projection 425 may be pivotably attached to the remainder of the hand retainer by a conventional pivot joint. Such rotational degree of freedom is additional to the adjustable translation of the hand retainer projection 425 along the channel 414.

FIGS. 13A-C depict different views of a force sensing resistor (FSR) 1300 according to an example embodiment of the present disclosure. As shown in the cross section of the FSR 1300 in FIG. 13C, the FSR 1300 may include a first substrate 1302 made of polyimide. The FSR 1300 may further include a second substrate 1304 disposed on (or over) the first substrate 1302. The first substrate 1302 and the second substrate 1304 may be considered to be the two primary substrates (or layers) of the FSR 1300, which can be considered a 2-layer FSR 1300, although it is to be appreciated that the FSR 1300 includes additional layers, as will be described in more detail herein. In this context, the first substrate 1302 may be considered a “bottom” or “base” substrate with respect to the two primary substrates of the FSR 1300, although it is to be appreciated that there may be layers of material behind (or below) the first substrate 1302 (i.e., in the negative Z direction, as depicted in FIG. 13C).

The first substrate 1302 has a conductive material disposed on a front surface (i.e., the surface facing in the positive Z direction) of the first substrate 1302. As will be described in more detail with reference to FIG. 14, this conductive material may include a plurality of interdigitated metal fingers. Meanwhile, the second substrate 1304 (sometimes referred to as a resistive “membrane”) has resistive material disposed on a back surface (i.e., the surface facing the negative Z direction) of the second substrate 1304. This resistive material may be a semiconductive material, such as an ink composition (e.g., silver ink, carbon ink, mixtures thereof, etc.), that exhibits some level of electrical resistance (e.g., a relatively high sheet resistance within a range of 300 kiloOhm (kOhm) per square (kOhm/sq) to 400 kOhm/sq). Preferably, the sheet resistance of the second substrate 1304 is 350 kOhm/sq, although it is to be appreciated that other sheet resistance values, including those outside of the sheet resistance ranges specified herein, may be used, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, the sheet resistance range(s) specified herein is to be understood as non-limiting. In some embodiments, the second substrate 1304 may be made of mylar, with the resistive material disposed on a back surface of the second substrate 1304. In some embodiments, the second substrate 1304 is made of polyimide having a resistive material (e.g., a conductive ink composition) on the back surface. An example benefit of using polyimide for the second substrate 1304 is to create an FSR 1300 that can be mass manufactured using a reflow oven, whereas mylar could not withstand such high temperatures.

The FSR 1300 may include one or more spacer layers interposed between the first substrate 1302 and the second substrate 1304 so that a center portion of the second substrate 1304 is suspended over the first substrate 1302 and spaced a distance therefrom. FIG. 13C shows two spacer layers including, without limitation, a coverlay 1306 disposed on the first substrate 1302 at a periphery of the first substrate 1302, and a layer of adhesive 1308 disposed on the coverlay 1306. The coverlay 1306 may be made of polyimide, and may thus be the same material as the first substrate 1302. A thickness (as measured in the Z direction) of the coverlay 1306 may be within a range of 10 microns to 15 microns. A thickness (as measured in the Z direction) of the layer of adhesive 1308 may be within a range of 50 microns to 130 microns. The total distance at which the second substrate 1304 is spaced from the first substrate 1302 may, therefore, be the sum of the thicknesses of the one or more spacer layers (e.g., the thickness of the coverlay 1306 plus the thickness of the layer of adhesive 1308). These layers may be provided at thicknesses that are outside of the thickness ranges specified herein, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, these thickness ranges are to be understood as non-limiting.

An actuator 1310 (such as a disk-shaped, compliant plunger) may be disposed on the second substrate 1304, and is configured to convey a force, F, onto a front surface of the second substrate 1304. The actuator 1310 can be made of Poron, which is a compliant material that deforms to a degree upon application of a force upon the actuator 1310. The actuator 1310 may be concentric with a center of an active area of the FSR 1300 in order to center the applied force, F. The actuator 1310 also spans a portion of the active area of the FSR 1300 in order to evenly distribute the applied force, F, across that portion of the active area of the FSR 1300.

A thickness (as measured in the Z direction) of the second substrate 1304 may be within a range of 50 microns to 130 microns. At this example thickness, the second substrate 1304 is flexible. For example, the second substrate 1304 can be made of mylar, which is flexible at a thickness within the above-specified range. Functional operation of the FSR 1300 relies on the flexibility of the second substrate 1304 in order for the resistive material on the back surface of the second substrate 1304 to come into contact with the conductive material on the front surface of the first substrate 1302 under a compressive force, F, applied to the actuator 1310. A thickness (as measured in the Z direction) of the first substrate 1302 may be within a range of 20 microns to 30 microns. Polyimide, at this thickness, is also flexible. Thus, the first substrate 1302 is also flexible. Meanwhile, a thickness (as measured in the Z direction) of the actuator 1310 may be within a range of 780 microns to 810 microns. These layers may be provided at thicknesses that are outside of the thickness ranges specified herein, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, these thickness ranges are to be understood as non-limiting.

The FSR 1300 may exhibit varying resistance in response to a variable force, F, applied to the actuator 1310. For example, as the force, F, on the actuator 1310 is increased, the resistance is decreased. In this manner, the FSR 1300 may be treated as a variable resistor whose value is controlled by the applied force, F. The FSR 1300 can be a “ShuntMode” FSR 1300 or a “ThruMode” FSR 1300, but is preferably a ShuntMode FSR 1300. With a ShuntMode FSR 1300, the conductive material disposed on the front surface of the first substrate 1302 may be in the form of a plurality of interdigitated metal fingers. When the force, F, is applied to the front (or top) of the actuator 1310, the resistive material on the back surface of the second substrate 1304 comes into contact with some of the interdigitated metal fingers, which shunts the metal fingers, thereby varying the resistance across the output terminals of the FSR 1300. In a ThruMode implementation, the conductive material on the first substrate 1302 may be a solid area of conductive material with a semiconductive (or resistive) material disposed on the conductive material, and the second substrate 1304 may have a similar construction (e.g., a solid area of conductive material having a semiconductive (or resistive) material disposed thereon). The solid area of conductive material on each substrate (1302 and 1304) is coupled to an individual output terminal, and excitation current can pass through one layer to the other when the two substrates (1302 and 1304) come into contact under an applied force, F.

In at least the preferred ShuntMode implementation, the Force vs. Resistance response curve—where the FSR 1300 resistance is plotted as a function of applied force, F—exhibits desirable characteristics for use in a controller 100/600 of a VR system. For instance, the response curve of the FSR 1300 may exhibit less hysteresis and higher repeatability (from one FSR 1300 to another FSR 1300), as compared to conventional FSRs, such as those that use mylar as the material for the bottom substrate. Loading hysteresis describes the effect of previously applied forces on the current FSR 1300 resistance. The response curve is also monotonic, and it models a true analog input that can be leveraged for a number of game mechanics in a VR gaming system, such as to crush a virtual rock, squeeze a virtual balloon, etc. It is to be appreciated that although examples herein describe an applied force, F, the FSR 1300 is, in actuality, sensitive to applied pressure (force×area) because equal amounts of force applied at a small point verses a larger area on front surface of the second substrate 1304 will result in a different resistance response of the FSR 1300. Thus, the actuator 1310 plays a role in maintaining repeatability across FSRs 1300 in terms of the response curves under applied force, F.

FIG. 14 depicts various front views of the FSR 1300 at progressive stages in an example process of constructing the FSR 1300. At Stage 1 of FIG. 14, a plurality of interdigitated metal fingers 1400 may be formed on a front surface of the first substrate 1302 of polyimide. The metal fingers 1400 are electrically conductive. An example conductive metal used for the metal fingers 1400 is copper, such as ⅓ oz. HA copper. This copper may also be gold plated. The plurality of interdigitated metal fingers 1400 may be formed using a subtractive manufacturing process. For example, prior to Stage 1, the first substrate 1302 of polyimide may be formed with a copper clad layer disposed on its front surface, and the copper clad layer may be etched (e.g., by removing strips of copper material) to create the pattern of interdigitated metal fingers 1400 shown in Stage 1 of FIG. 14. The size and spacing of the etched pattern may be chosen to create a distance (as measured in the Y direction) between pairs of adjacent metal fingers 1400 that is 0.2 millimeters (mm), and a width (as measured in the Y direction) of each metal finger of the plurality of interdigitated metal fingers 1400 that is 0.2 mm. This finger width and spacing between fingers may provide an optimal balance between maximum sensitivity of the FSR 1300 and a minimized manufacturing etch tolerance. Although a uniform pattern of metal fingers 1400 is shown in FIG. 14, it is to be appreciated that other non-uniform patterns (e.g., denser fingers toward a center, and less dense fingers toward the outside) may be employed. FIG. 14 shows two sets of interdigitated metal fingers 1400, each leading to an output terminal 1402 (or lead) of a 2-terminal FSR 1300 having a first output terminal 1402(1) and a second output terminal 1402(2).

As mentioned, the copper that constitutes the metal fingers 1400 may be gold plated. Thus, after etching the pattern of interdigitated metal fingers 1400, a layer of gold plating may be deposited onto the copper fingers to create gold-plated fingers. Thus, the plurality of interdigitated metal fingers 1400 shown in Stage 1 of FIG. 14 can represent gold-plated fingers. The gold-plating may be electroless nickel immersion gold (ENIG). Notably, there may be no additional copper plating over the base layer copper prior to gold plating. Additional copper plating is commonly applied atop the base layer copper when adding vias to multi-layer flex substrates. However, adding additional copper plating over the base layer copper prior to gold-plating may actually cause an undesirable increase of detected resistance, as compared to the disclosed FSR 1300 that does not include any additional copper plating over the base layer copper prior to gold plating. Thus, the omission of any additional copper plating on the metal fingers 1400 prior to the gold plating achieves optimal sensitivity in the FSR 1300. Thus, the copper clad layer that constitutes the metal fingers 1400 remains exposed at the time that the metal fingers 1400 are plated with gold material. In this manner, the gold material is in direct contact with the base copper material of the metal fingers 1400, without any additional copper plating interposed between the base layer copper and the gold plating.

At Stage 2 of FIG. 14, a coverlay 1306 can be deposited atop the first substrate 1302 at a periphery of the first substrate 1302. For example, the covelay 1306 can be annular in shape to cover a peripheral portion of the metal fingers 1400, and a remaining portion of the metal fingers 1400 is left uncovered by the coverlay 1306 after deposition. The coverlay 1306 may be made of polyimide.

At Stage 3 of FIG. 14, a layer of adhesive 1308 may be deposited atop the coverlay 1306 such that the remaining portion of the metal fingers 1400 (the portion of the metal fingers 1400 left uncovered by the coverlay 1306) is also left uncovered by the layer of adhesive 1308. For example, the layer of adhesive 1308 can be C-shaped so that the layer of adhesive 1308 covers a substantial portion of the coverlay 1306, and so that the layer of adhesive 1308 does not cover an active area of the FSR 1300. The “active area” of the FSR 1300 is shown in Stage 3 of FIG. 14 as having a diameter, B. Furthermore, the layer of adhesive 1308, being C-shaped, can leave a section of the coverlay 1306 uncovered by the layer of adhesive 1308. This uncovered section of the coverlay 1306 is shown in Stage 3 of FIG. 14 as having a width, w. After the second substrate 1304 is placed over the top of the first substrate 1302, this uncovered section of coverlay 1306 creates an air gap that allows air to ingress and/or egress from a space between the first substrate 1302 and the second substrate 1304, which may prevent sensor-to-sensor response variations due to changes in atmospheric pressure. The width, w, of the air gap (i.e., the uncovered section of the coverlay 1306) can be 1 mm, which is small enough to preserve symmetry of the contacted surface area under an applied force, and large enough to allow air to ingress/egress through the air gap. In some embodiments, the layer of adhesive 1308 may be 467 adhesive from 3M® Company of Maplewood, Minn. (i.e., 3M 467 adhesive). The coverlay 1306 and the layer of adhesive 1308 represent examples of spacer layers that can be provided atop the first substrate 1302 in order to space the second substrate 1304 a distance from the first substrate 1304 in a suspended fashion. As mentioned, a thickness (as measured in the Z direction) of the coverlay 1306 may be within a range of 10 microns to 15 microns, and a thickness (as measured in the Z direction) of the layer of adhesive 1308 may be within a range of 50 microns to 130 microns. Preferably, the thickness of the layer of adhesive 1308 is made as thin as possible (e.g., at the lower end of the specified thickness range) to allow for an initial response (e.g., the FSR 1300 starts detecting an input) under a very light applied force, F. However, these layers may be provided at thicknesses that are outside of the thickness ranges specified herein, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, these thickness ranges are to be understood as non-limiting.

At Stage 4, a second substrate 1304 can be provided atop the first substrate 1302. In Stage 4, a center portion of the second substrate 1304 is suspended over the first substrate 1302 by virtue of the one or more spacer layers (e.g., the coverlay 1306 and the layer of adhesive 1308) interposed between the first substrate 1302 and the second substrate 1304 (See FIG. 13C). Although it is not shown in FIG. 14, the actuator 1310 can be attached to the front surface of the second substrate 1304 in order to complete the construction of the FSR 1300, as shown in FIGS. 13A-C. The size (as measured in the X-Y plane) of the actuator may span 80% of the active area of the FSR 1300 (i.e., 80% of the diameter, B, shown in Stage 3 of FIG. 14). For instance, a disk shaped actuator 1310 may have a diameter that is equal to 0.8*B. In some embodiments, the overall diameter of the FSR 1300 may be 14.5 mm. At this dimension, the active area may have a diameter, B, of 10.5 mm, meaning that the coverlay 1306 and the layer of adhesive 1308 may be deposited as a 2 mm ring between the first substrate 1302 and the second substrate 1304. In this embodiment, the actuator 1310 may have a diameter of 8.4 mm (i.e., 0.8*10.5 mm).

The FSR 1300 may be open-circuit under no external force (or load). In some embodiments, in order to account for any contact of the first substrate 1302 and the second substrate 1304 under zero or negligible applied force, a threshold circuit can be used to set a threshold resistance value at which the first substrate 1302 and the second substrate 1304 are considered to be “in contact,” meaning that the FSR 1300 can be open-circuit until the threshold resistance value is met, even if the two primary substrates (i.e., 1302 and 1304) are actually in contact.

FIG. 15 depicts example layers of a FSR 1300, according to another embodiment of the present disclosure. FIG. 15 is not to scale. Rather, FIG. 15 is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR 1300. As described above with reference to the previous figures, the FSR 1300, as shown in FIG. 15, includes a first substrate 1302 made of polyimide, metal fingers 1400 (i.e., a conductive material) disposed on the front surface of the first substrate 1302, and a second substrate 1304 disposed on the first substrate 1302, with one or more spacer layers interposed between the first substrate 1302 and the second substrate 1304; in this case, there are multiple spacer layers disposed between the two primary substrates, including the aforementioned coverlay 1306 and the layer of adhesive 1308. An actuator 1310 is also disposed on the second substrate 1304.

In the embodiment of FIG. 15, the actuator 1310 may be made of Poron, and may have a thickness (as measured in the Z direction) of 794 microns. A layer of actuator adhesive 1500 may be used to attach the actuator 1310 to the second substrate 1304. This actuator adhesive 1500 can be 70 microns in thickness (as measured in the Z direction). A suitable adhesive for the actuator adhesive 1500 is FT 8397 adhesive from Avery Dennison of Glendale, Calif. In the embodiment of FIG. 15, the thickness (as measured in the Z direction) of the second substrate 1304 may be 125 microns. The sheet resistance of the resistive material on the back surface of the second substrate 1304 may be 350 kOhm/sq. The layer of adhesive 1308 may be a peel-off adhesive, such as 3M MP467 adhesive. The thickness (as measured in the Z direction) of the layer of adhesive 1308 may be 50 microns. The coverlay 1306 may be made of polyimide, and may have a thickness (as measured in the Z direction) of 12.5 microns. A coverlay adhesive 1502 (e.g., polyethylene with adhesive on either side) may be used to attach the coverlay 1306 to the front surface of the first substrate 1302 atop the metal fingers 1400. The coverlay adhesive 1502 may have a thickness (as measured in the Z direction) of 25 microns. The metal fingers 1400 may be made of copper (e.g., gold-plated copper) and may have a thickness (as measured in the Z direction) of 12.5 microns. The first substrate 1302 may have a thickness (as measured in the Z direction) of 25 microns.

A pressure sensitive adhesive (PSA) 1504 may be attached to a back surface of the first substrate 1302. The PSA 1504 may be 3M 467MP, and may have a thickness of 50 microns. A PSA liner 1506 may be disposed over the PSA 1504, and may be peeled off before attaching the FSR 1300 to a planar surface (e.g., to a planar surface of a structure mounted inside of a controller body 110).

At a connector portion of the FSR 1300, a stiffener polyimide 1508 may be attached to the back surface of the first substrate 1302 using a stiffener adhesive 1510. The stiffener polyimide 1508 may have a thickness (as measured in the Z direction) of 137.5 microns, and may create a stiffer connector portion of the FSR 1300 for added durability of the connector portion. The thickness (as measured in the Z direction) of the stiffener adhesive may be 25 microns.

The embodiment of FIG. 15 may represent a FSR 1300 that is suitable for mounting on a planar surface of a structure that is mounted within a handle 112/612 of a controller 100/600 for an electronic system (e.g., a VR system), as disclosed herein. It is to be appreciated that other thickness values, sheet resistance values, and/or materials than those specified with reference to FIG. 15 may be utilized, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, these values and materials are to be understood as non-limiting.

FIG. 16 depicts example layers of a FSR 1300, according to another embodiment of the present disclosure. FIG. 16 is not to scale. Rather, FIG. 16 is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR 1300. The FSR 1300 shown in FIG. 16 with respect to the first substrate 1302 and the layers above (i.e., in the positive Z direction) the first substrate 1302 may be have a similar construction to the FSR 1300 shown in FIG. 15. FIG. 16 differs from FIG. 15 in the layers below (i.e., in the negative Z direction) the first substrate 1302. Thus, for purposes of brevity, the first substrate 1302 and the layers above (i.e., in the positive Z direction) the first substrate 1302 in FIG. 16 will not be described again, as reference can be made to the description of FIG. 15 for these layers in FIG. 16.

In the embodiment of FIG. 16, a stiffener 1600 may be attached to the back surface of the first substrate 1302 underneath the main body portion of the FSR 1300 using a stiffener adhesive 1510. The thickness (as measured in the Z direction) of the stiffener adhesive may be 25 microns, as is the case in the embodiment of FIG. 15, but the stiffener 1600 is located underneath the main body portion of the FSR 1300, whereas the stiffener polyimide 1508 is located underneath a connector portion of the FSR 1300. Furthermore, the stiffener 1600 may be a FR4 stiffener having a thickness (as measured in the Z direction) of 530 microns, which is thicker than the stiffener polyimide 1508 of the embodiment of FIG. 15. A pulltab 1602 may be attached to the back surface of the stiffener 1600 using a layer of adhesive 1604. The layer of adhesive 1604 may be a pulltab adhesive, such as 3M MP467 adhesive. The thickness (as measured in the Z direction) of the layer of adhesive 1604 may be 50 microns.

The embodiment of FIG. 16 may represent a FSR 1300 that is suitable for mounting on a planar surface of a structure that is mounted underneath a thumb-operated control 116 of a controller 100/600 for an electronic system (e.g., a VR system), as disclosed herein. It is to be appreciated that other thickness values, sheet resistance values, and/or materials than those specified with reference to FIG. 16 may be utilized, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, these values and materials are to be understood as non-limiting.

FIG. 17 depicts example layers of a FSR 1300, according to another embodiment of the present disclosure. FIG. 17 is not to scale. Rather, FIG. 17 is presented to illustrate example layers of material, and is not meant to represent an actual cross-sectional view of the FSR 1300. Some of the layers of the FSR 1300 shown in FIG. 17 may be have a similar construction to the FSR 1300 shown in FIG. 15. FIG. 17 differs from FIG. 15 several aspects, however.

In the embodiment of FIG. 17, the thickness (as measured in the Z direction) of the second substrate 1304 may be 127 microns. The layer of adhesive 1308 may be a peel-off adhesive, such as 3M 468MP adhesive. For a FSR 1300 that can withstand high temperatures of a reflow oven, the layer of adhesive 1308 may be a peel-off adhesive, such as 3M 9085, or 3M 9082. The thickness (as measured in the Z direction) of the layer of adhesive 1308 may be 125 microns. In some cases, the thickness of the layer of adhesive 1308 may be 50 microns. In addition, the metal fingers 1400 may be made of RA copper. In addition, a conductive material 1700 may be disposed on a back surface of the first substrate 1302. The conductive material 1700 may be HA copper or RA copper having a thickness (as measured in the Z direction) of 12.5 microns. An additional coverlay 1702 may be deposited on the conductive material 1700. This additional coverlay 1702 may be made of polyimide, and may be attached to the conductive material 1700 using a coverlay adhesive 1704. The thickness (as measured in the Z direction) of the additional coverlay 1702 may be 12.5 microns, and a thickness (as measured in the Z direction) of the coverlay adhesive 1704 may be 25 microns. A layer of adhesive 1706 may be disposed on the coverlay 1702. The layer of adhesive 1706 may be a peel-off adhesive, such as 3M 467MP adhesive, at a thickness (as measured in the Z direction) of 60 microns. For a FSR 1300 that can withstand high temperatures of a reflow oven, the layer of adhesive 1706 may be a peel-off adhesive, such as 3M 9085, or 3M 9082.

The embodiment of FIG. 17 may represent a FSR 1300 that is suitable for mounting on a planar surface of a structure that is mounted within a controller body 110 of a non-VR controller. It is to be appreciated that other thickness values, sheet resistance values, and/or materials than those specified with reference to FIG. 17 may be utilized, such as when the FSR 1300 is used in other applications, such as non-controller based applications. As such, these values and materials are to be understood as non-limiting.

FIGS. 18A-D depict a FSR 1800, according to another embodiment of the present disclosure. The FSR 1800 may have component layers that are similar to those described with reference to the FSR 1300, such as a first substrate 1802 made of polyimide, and a second substrate 1804 that is flexible and that has a resistive material on its back surface. One or more spacer layers (e.g., a coverlay 1806 and a layer of adhesive 1808) may be interposed between the first substrate 1802 and the second substrate 1804.

A portion of the first substrate 1802 of the FSR 1800 in FIGS. 18B and 18C is wrapped around the second substrate 1804 and is also disposed on a front surface of the second substrate 1804. FIG. 18A is labeled “Before Fold” and depicts the FSR 1800 before the portion of the first substrate 1802 is wrapped around the second substrate 1804. In FIG. 18A, the FSR 1800 includes a first body portion 1812(1) (sometimes referred to as the “lower balloon” 1812(1)) and a second body portion 1812(2) (sometimes referred to as the “upper balloon” 1812(2)). The lower balloon 1812(1) is connected to the upper balloon 1812(2) by a folding neck 1814 at a first end of the lower balloon 1812(1). A soldering pigtail 1816 extends from a second end of the lower balloon 1812(1) and soldering pads 1818 are on the terminal end of the soldering pigtail 1816. An actuator 1810 in the form of a tact switch is disposed on the upper balloon 1812(2) such that the actuator 1810 ends up being the front or top layer of the FSR 1800 after the folding operation, as shown in FIGS. 18B and 18C. Thus, the portion of the first substrate 1802 of the FSR 1800 that is wrapped around the second substrate 1804 is the upper balloon 1812(2).

A cross section of the FSR 1800, after the folding operation, is shown in FIG. 18C to depict example layers of the FSR 1800. Some of the layers shown in FIG. 18C are described in more detail with reference to FIG. 18D. In this embodiment of FIG. 18C, a force, F, can be applied to the actuator 1810 (e.g., tact switch), causing a variable resistance of the FSR 1800 that is converted into a variable digitized value. The use of a tact switch for the actuator 1810 (e.g., a switch that toggled to a different binary state under the application of a predefined amount of force, F) creates a dual-stage FSR 1800 that first “clicks” when the tact switch 1810 is actuated, and then the FSR 1800 can output variable resistance as increased force, F, is applied. This can serve to calibrate the FSR 1800 on individual actuations of the FSR 1800 by assuming that the tact switch 1810 actuates at a same amount of force, F, each time it is depressed. That is, the FSR 1800 can reset to the known amount of force, F, associated with actuation of the tact switch 1810 in response to detecting an actuation of the tact switch 1810. This can mitigate inherent inaccuracy of the FSR 1800.

As shown in FIGS. 18C and 18D, the FSR 1800 includes a first substrate 1802 made of polyimide having a thickness (as measured in the Z direction) of 25 microns. A conductive material (e.g., the metal fingers 1820 made of HA copper (e.g., gold-plated copper) shown in FIG. 18D) having a thickness (as measured in the Z direction) of 12.5 microns may be disposed on the front surface of the first substrate 1802 at the lower balloon 1812(1) such that the conductive material is underneath the resistive material on the second substrate 1804. A coverlay adhesive 1822 may be used to attach the coverlay 1806 to the front surface of the first substrate 1802 atop the metal fingers 1820. The coverlay adhesive 1822 may have a thickness (as measured in the Z direction) of 25 microns. The coverlay 1806 may be made of polyimide, and may have a thickness (as measured in the Z direction) of 12.5 microns. The layer of adhesive 1808 disposed on the coverlay 1806 may be a peel-off adhesive, such as 3M MP467 adhesive. The thickness (as measured in the Z direction) of the layer of adhesive 1808 may be 60 microns. The thickness (as measured in the Z direction) of the second substrate 1804 may be 127 microns. The sheet resistance of the resistive material on the back surface of the second substrate 1804 may be 350 kOhm/sq. A layer of adhesive 1824 may be used to attach the upper balloon 1812(2) to the lower balloon 1812(1) when the upper balloon 1812(2) is folded over the lower balloon 1812(1) at the folding neck 1814. The layer of adhesive 1824 can be 125 microns in thickness (as measured in the Z direction). A suitable adhesive for the layer of adhesive 1824 is 3M 468MP. The layer of adhesive 1824 may also be C-shaped.

On the upper balloon 1812(2) of the FSR 1800, a first stiffener polyimide 1834 may be attached to the front surface of the first substrate 1802 (before folding) using a stiffener adhesive 1836. The first stiffener polyimide 1834 may have a thickness (as measured in the Z direction) of 75 microns. The thickness (as measured in the Z direction) of the stiffener adhesive may be 25 microns. In addition, on the upper balloon 1812(2) of the FSR 1800, a second stiffener polyimide 1838 may be attached to the front surface of the first stiffener polyimide 1834 (before folding) using a layer of adhesive 1840. The second stiffener polyimide 1838 may have a thickness (as measured in the Z direction) of 75 microns. The thickness (as measured in the Z direction) of the layer of adhesive may be 125 microns. When the upper balloon 1812(2) is folded over the lower balloon 1812(1) at the folding neck 1814, the second stiffener polyimide 1838 comes into contact with the second substrate 1804, as shown in FIG. 18C, and the layer of adhesive 1824 adheres the two main body portions 1812(1) and 1812(2) of the FSR 1800 in a stacked relationship after the folding operation. It is to be appreciated that other thickness values, sheet resistance values, and/or materials than those specified with reference to FIG. 18D may be utilized, such as when the FSR 1800 is used in other applications, such as non-controller based applications. As such, these values and materials are to be understood as non-limiting

In addition, as shown in FIG. 18D, a conductive material 1826 may be disposed on a back surface of the first substrate 1802. The conductive material 1826 may be HA copper having a thickness (as measured in the Z direction) of 12.5 microns. An additional coverlay 1828 may be deposited on the conductive material 1826. This additional coverlay 1828 may be made of polyimide, and may be attached to the conductive material 1826 using a coverlay adhesive 1830. The thickness (as measured in the Z direction) of the additional coverlay 1828 may be 12.5 microns, and a thickness (as measured in the Z direction) of the coverlay adhesive 1830 may be 25 microns. The additional coverlay 1828 and the coverlay adhesive 1830 may span the soldering pigtail 1816, the lower balloon 1812(1), the folding neck 1814, and a portion of the upper balloon 1812(2), leaving a footprint (or space) for the actuator 1810 (“Button Footprint” in FIG. 18D). A layer of adhesive 1832 may be disposed on the additional coverlay 1828. The layer of adhesive 1832 may be a peel-off adhesive, such as 3M 468MP adhesive, at a thickness (as measured in the Z direction) of 125 microns. The layer of adhesive 1832 may span the soldering pigtail 1816 and the lower balloon 1812(1).

Although the example FSR 1300/1800 is shown as having a generally circular shape, it is to be appreciated that the FSR 1300/1800 can be constructed in layers of different cross-sectional shapes, such as square, rectangular, etc. The FSR 1300/1800 can be larger or smaller in overall size than the examples described herein, depending on the particular application. Furthermore, it is to be appreciated that arrays of FSRs can be implemented by connecting multiple FSRs 1300/1800 together. In such an array, the layers of FSR material may be constructed in a long strip of material.

FIG. 19 is a flow diagram of an example process 1900 for manufacturing a FSR, such as the FSR 1300 or the FSR 1800 disclosed herein. The processes described herein are illustrated as a collection of blocks in a logical flow graph, which represent a sequence of operations. The order in which the operations are described is not intended to be construed as a limitation, and any number of the described blocks can be combined in any order and/or in parallel to implement the processes.

At 1902, a first substrate 1302 made of polyimide may be formed with copper clad layer disposed on a front surface of the first substrate 1302.

At 1904, the copper clad layer may be etched to form a plurality of interdigitated copper fingers (i.e., an example of the metal fingers 1400) on the front surface of the first substrate 1302. The etching at block 1904 may include removing strips of copper material having a width of 0.2 mm to create a distance of 0.2 mm between pairs of adjacent copper fingers among the plurality of interdigitated copper fingers. The spacing between sequential strips of removed copper material may also be kept at 0.2 mm to provide copper fingers having a width of 0.2 mm.

At 1906, a layer of gold plating may be deposited onto the plurality of interdigitated copper fingers to create gold-plated fingers. This gold plating may be ENIG.

At 1908, one or more spacer layers may be provided atop the first substrate 1302 at a periphery of the first substrate 1302, thereby leaving a portion of the gold-plated fingers uncovered by the one or more spacer layers. As shown by the sub-blocks 1910 and 1912, multiple spacer layers may be provided in two operations.

At 1910, a coverlay 1306 (e.g., made of polyimide) may be deposited on the first substrate 1302 at a periphery of the first substrate. The coverlay 1306 may cover a peripheral portion of the gold-plated fingers, wherein a remaining portion of the gold-plated fingers is left uncovered by the coverlay 1306.

At 1912, a layer of adhesive 1308 may be deposited on the coverlay 1306 such that the remaining portion of the gold-plated fingers is left uncovered by the layer of adhesive 1308. Furthermore, the operation at block 1912 may include leaving a section of the coverlay 1306 uncovered by the layer of adhesive 1308 to create an air gap that allows air to ingress or egress from a space between the first substrate 1302 and the second substrate 1304.

At 1914, a second substrate 1304 may be provided atop the first substrate 1302 such that a center portion of the second substrate 1304 is suspended over the first substrate 1302 by the one or more spacer layers interposed between the first substrate 1302 and the second substrate 1304. This second substrate 1304 is flexible and has resistive material disposed on a back surface of the second substrate 1304.

At 1916, in order to construct the FSR 1800, an extended portion of the first substrate 1802 may be wrapped around the second substrate 1804 and attached to the front surface of the second substrate 1804, where the extended portion of the first substrate 1802 is to be interposed between a to-be-attached actuator 1810 and the second substrate 1804. As shown by the dotted outline of block 1916, this operation is performed to construct the FSR 1800, but may be omitted when constructing the FSR 1300.

At 1918, an actuator 1310 may be provided atop the second substrate 1304, such as by attaching the actuator 1310 to a front surface of the second substrate 1304 to construct the FSR 1300, or by attaching the actuator 1810 (e.g., a tact switch), to the first substrate 1802 that is interposed between the first substrate second substrate 1804 and the actuator 1810.

The FSR 1300/1800 disclosed herein may be mounted on a planar surface of a structure within a handheld controller, such as the controller 100/600 disclosed herein, and this structure can be positioned at any suitable location within the controller body 110 in order to measure a resistance value that corresponds to an amount of force applied to an outer surface of the controller body 110 (e.g., a force applied by a finger pressing upon a control, a force applied by a hand squeezing the handle 112/612. With specific reference to FIGS. 9A and 9B, the FSR 1300/1800 can be mounted on a planar surface of the PCB 920, which itself may be mounted within the tubular housing 612 a, 612 b of the handle 612. In this configuration, the plunger 924 may interface with the actuator 1310/1810 of the FSR 1300/1800, which may allow for conveying a compressive force from the plunger 924 to the actuator 1310/1810. Other configurations are possible, however, where the plunger 924 is omitted, and the actuator 1310/1810 interfaces with a portion of the tubular housing 612 a, 612 b of the handle 612. With specific reference to FIG. 1, a FSR 1300/1800 can be mounted on a planar surface of a structure within a head (between the handle 112 and a distal end 111). The structure mounted within a head may be mounted underneath one or more of the thumb-operated controls 114, 115, 116. For example, the FSR 1300/1800 can be positioned underneath the thumb-operated control 116 (e.g., a track pad). Accordingly, when a user's thumb presses upon the thumb-operated control 116 during operation while the controller 100, the FSR 1300/1800 positioned underneath the thumb-operated control 116 may be configured to measure a resistance value that corresponds to an amount of force applied to the thumb-operated control 116 by the user's thumb. It is to be appreciated that multiple FSRs 1300/1800 can be disposed within the controller body 110 of the controller, such as one or more FSRs 1300/1800 mounted within the handle 112/612 and one or more FSRs 1300/1800 mounted underneath one or more corresponding controls 114, 115, 116 on the head of the controller body 110.

The FSR 1300/1800 disclosed herein may enable variable analog inputs when implemented in a controller 100/600. For instance, squeezing the handle 112/612 or pressing upon the thumb-operated control(s) (e.g., 116) with varying amount of force may cause resistance of the FSR 1300/1800 to vary with the applied force, and the resistance can be converted to a varying digitized value that represents the FSR input for controlling a game mechanic.

FIG. 20 illustrates an example user interface (UI) 2000 that may be used to configure a FSR-based input mechanism of a handheld controller, such as the controller 100/600, for an electronic system to operate in different modes. The UI 2000 may be output on a display of an electronic system, such as a head mounted display (HMD), or any other type of display used with a personal computer (PC) or a game console. The UI 2000 includes an “Activation Type” drop down menu 2002. The “Activation Type” drop down menu 2002 may be used to select a “Soft Press” type of activation for a FSR-based input mechanism (e.g., the thumb-operated control 116, the handle 112/612, etc.). Here, “Soft Press” means “software press,” which allows the controller 100/600 and/or the electronic system with which the controller 100/600 is associated to determine, using logic, when to register a FSR-based input event based on the analog input of the FSR 1300/1800 (e.g., the FSR resistance, which corresponds to the applied force on the FSR 1300/1800, and which is converted to a digitized FSR input value), and also based on the additional configuration settings that will be discussed shortly. In other words, a resistance value can be measured by the FSR 1300/1800, which can be converted into a digitized FSR input value. If this digitized FSR input value meets a criterion specified by the configuration settings for the “Soft Press,” a FSR-based input event can be registered.

The UI 2000 may further include a “Binding” drop down menu 2004, which may be used to select a PC-based input control to bind to the corresponding FSR-based input mechanism on the controller 100/600. Here, the binding is selected as the Left Mouse button, but it is to be appreciated that the binding can be selected as other PC-based input controls. The binding can also be analog. For example, for a racing game, the FSR 1300/1800 can be used for the gas pedal (e.g., the harder the user presses upon a FSR-based control mechanism, the faster the racing vehicle goes in the game).

The UI 2000 may further include a “Soft Press Style” drop down menu 2006, which may be used to select one of various styles of a Soft Press. A “Simple Threshold” style means that a FSR input event occurs when the digitized FSR input value meets or exceeds a threshold value. Because the digitized FSR input value corresponds to a particular resistance value measured by the FSR, which, in turn, corresponds to a particular amount of force applied to the FSR 1300/1800, one can also think of this style of Soft Press as registering a FSR input event when the resistance value measured by the FSR meets a threshold resistance value, and/or when the applied amount of force meets a threshold amount of force. For example, if the handle 112/612 of the controller 100/600 includes a FSR 1300/1800, the handle 112/612 can be squeezed until a threshold amount of force is reached, and, in response, a FSR input event is registered as a “Soft Press.” The force required to “unpress” may be a fraction of the threshold value for debounce purposes and/or to mimic a tact switch with a physical snap ratio. The “Simple Threshold” style may therefor replace a conventional mechanical switch. The UI 200 shows that a configurable Soft Press Threshold 2008(1) can be adjusted by the user to increase or decrease a threshold value that is compared to digitized FSR input values to determine whether to register a FSR input event. The user can adjust the Soft Press Threshold 2008(1) lower (e.g., by moving the slider to the left) in order to reduce hand fatigue relating to actuation of the FSR-based input mechanism. The user can adjust the Soft Press Threshold 2008(1) higher (e.g., by moving the slider to the right) in order to reduce the instances in which an accidental input is registered by the FSR-based input mechanism. In some cases, the Soft Press Threshold 2008(1) can be set to a default threshold value for a particular game (e.g., a lower default threshold value for a shooting game, a higher default threshold value for an exploration game, etc.).

A “Hair Trigger” style may set a baseline threshold value, and once a digitized FSR input value associated with the FSR 1300/1800 meets or exceeds the baseline threshold value, the binding is activated (i.e., a FSR input event is registered, akin to a press-and-hold button actuation). Thereafter, any subsequent decrease in force deactivates the binding (i.e., the FSR input event is “unregistered,” akin to a user letting go of a button), and any increase in force after deactivating the binding operates to activate the binding again. There may be some debounce in the “Hair Trigger” style of Soft Press. Turning briefly to FIG. 21, an example of the “Hair Trigger” logic is shown on a Force vs. Time graph 2100. The Force axis may represent digitized FSR input values ranging from zero to any suitable maximum value, which corresponds to a range of resistance values that are measurable by the FSR 1300/1800. As shown in FIG. 21, as the digitized FSR input value increases (e.g., the user presses harder and harder on the FSR-based input mechanism), the digitized FSR input value eventually crosses the baseline threshold value 2102, and, in response, the binding is activated (i.e., a FSR input event is registered akin to a press-and-hold type of user input), and thereafter, the binding is deactivated in response to a decrease in the digitized FSR input value (e.g., the user “lets up” slightly on the FSR-based input mechanism). If the user presses harder upon the FSR-based input mechanism, the binding may be activated again, and so on and so forth, as long as the force remains at a value that is greater than the baseline threshold value 2102.

With reference again to FIG. 20, a “Hip Fire” style of Soft Press may be selected in three different sub-styles (e.g., Aggressive, Normal, and Relaxed). The “Hip Fire” style may be similar to the “Simple Threshold” style of Soft Press, except that the “Hip Fire” style utilizes a time delay so that, in a configuration with multiple levels of bindings, the time delay can be used to ignore lower FSR input values if a higher threshold value is reached quickly enough. The amount of time delay varies between the different sub-styles (e.g., Aggressive, Normal, and Relaxed). Turning briefly to FIG. 22, an example of the “Hip Fire” logic is shown on a Force vs. time graph 2200. Again, the Force axis may represent a range of digitized FSR input values from zero to any suitable maximum value, which corresponds to a range of resistance values that are measurable by the FSR 1300/1800. As shown in FIG. 22, assume that A1 2202 corresponds to a first threshold value that corresponds to a first action, and A2 2204 corresponds to a second threshold value that corresponds to a second action. A time delay, t, can be set based on whether the Hip Fire style is the Aggressive type, the Normal type, or the Relaxed type. In the “Fast” curve shown in FIG. 22, the FSR input values reach A1 2202 quickly, which triggers the time delay to start running. The FSR input values then reach A2 2204 before the time delay has lapsed, which causes the logic to ignore A1 2202 and to register a FSR input event exclusively for the second action that corresponds to A2 2204. In the “Slow” curve shown in FIG. 22, the FSR input values reach A1 2202, and the time delay is started. However, because the FSR input values do not increase fast enough to reach A2 2204 before the time delay lapses, the logic registers a FSR input event for the first action that corresponds to A1 2202, and, thereafter, the FSR input values eventually reach A2 2204, and the logic registers an additional FSR input event for the second action that corresponds to A2 2204. The time delay, t, may be specified in milliseconds, and is configurable.

With reference again to FIG. 20, an additional Soft Press Threshold 2008(2) may be usable, for example, to set a multi-level threshold, such as the thresholds for the “Hip Fire” style of Soft Press. The different styles of Soft Press for FSR-based input can be used to enable a number of different game-related, analog inputs by virtue of the user squeezing or pressing a FSR-based input mechanism with varying force. For example, a VR game can allow a user to crush a rock or squeeze a balloon by squeezing the handle 112/612 of the controller body 110 with increasing force. As another example, a shooting-based game may allow the user to toggle between different types of weapons by pressing a thumb-operated control 116 with different levels of applied force.

FIG. 23 depicts the controller 100 of FIG. 1 having various sensors disposed within the controller body 110. For example, a first FSR 1300(1) may be mounted underneath a control that is configured to be pressed, such as the thumb-operated control 116 that is included on a head 113 of the controller body 110. A second FSR 1300(2) may be mounted within the handle 112 of the controller body 110, along with an array of proximity sensors 800. It is to be appreciated that one or the other FSR 1300(1) or 1300(2) may be provided within the controller 100, or both FSRs 1300(1) and 1300(2) may be provided within the controller 100. In addition, or alternatively to array of proximity sensors 800, one or more touch sensors 2300 (e.g., touch sensors 2300(1)-(3)) may be associated with one or more controls that are configured to be pressed, such as the thumb-operated control 114, the thumb-operated control 115, and/or the thumb-operated control 116, and/or a finger-operated control (e.g., a trigger 609). The touch sensor(s) 2300 may be configured to provide touch data indicative of an object (e.g., a finger, a thumb, etc.) contacting an associated control (e.g., one or more of the thumb-operated controls 114-116). In an example, the touch sensor(s) 2300 comprises a capacitive sensor (or array of capacitive sensors) that is mounted within the head 113 of the controller body 110 (e.g., adhered or otherwise attached to a back surface of the outer housing and underneath the controls 114-116, attached to a structure, such as a PCB, within the head 113, etc.). In other instances, the touch sensor(s) 2300 can be based on other touch-sensing technologies, such as an infrared or acoustic touch sensor. Meanwhile, the array of proximity sensors 800 that are spatially distributed on the handle 112 may be configured to provide proximity data indicative of a hand grasping the handle 112. The proximity sensors 800 can also use any suitable technology for sensing contact and/or proximity of the hand on/to the handle 112, as disclosed herein. The FSRs 1300 are configured to provide force data indicative of an amount of force of a press of a control (e.g., a press of the control 116), or a squeeze of the handle 112. Sets of the various sensors shown in FIG. 23 may be connected by a flex circuit. For example, the touch sensors 2300 and the FSR 1300(1) in the head 113 may be connected together by a common flex circuit. The polyimide substrate of the FSR 1300 disclosed herein allows for this type of direct soldering of the FSR output terminals to a flex circuit.

The processes described herein are illustrated as a collection of blocks in a logical flow graph, which represent a sequence of operations that can be implemented in hardware, software, or a combination thereof. In the context of software, the blocks represent computer-executable instructions that, when executed by one or more processors, perform the recited operations. Generally, computer-executable instructions include routines, programs, objects, components, data structures, and the like that perform particular functions or implement particular abstract data types. The order in which the operations are described is not intended to be construed as a limitation, and any number of the described blocks can be combined in any order and/or in parallel to implement the processes.

FIG. 24 is a flow diagram of an example process 2400 for re-calibrating a FSR 1300/1800 of a handheld controller 100/600 based on touch data provided by a touch sensor.

At 2402, logic of the handheld controller 100/600 may determine, based at least in part on touch data provided by a touch sensor, that an object (e.g., a finger, a thumb, etc.) has come into contact with at least one control of the handheld controller. The at least one control may be included on the controller body 110 of the controller 100/600 and may be configured to be pressed. For instance, the control may be the thumb-operated control 116 included on the head 113 of the controller body 110. In this embodiment, the touch sensor can be one of the touch sensors 2300. Alternatively, the control may be the handle 112 of the controller body 110. In this embodiment, the touch sensor can be the array of proximity sensors 800.

At 2404, the logic may determine, based at least in part on force data provided by a FSR 1300/1800 at a time at which the object has come into contact with the at least one control, a resistance value measured by the FSR 1300/1800.

At 2406, the logic may correlate the resistance value with a digitized FSR input value of zero. In other words, the sensed resistance when the object comes into contact with the at least one control can be taken as a force input of zero, meaning that any increase in force applied to the FSR 1300/1800 after that point is correlated with a positive FSR input value. Thus, the process 2400 represents a sensor fusion algorithm that can help mitigate any inherent inaccuracy of the FSR 1300/1800—which might measure some resistance even when an object is not pressing upon the control—through recalibration on the detection of a touch of the control.

FIG. 25 is a flow diagram of an example process 2500 for ignoring spurious input at a FSR 1300/1800 of a handheld controller 100/600 based on touch data provided by a touch sensor for an adjacent control.

At 2502, logic of a handheld controller 100/600 may determine, based at least in part on force data provided by a FSR 1300/1800 associated with a first control (e.g., thumb-operated control 116) of the handheld controller, a resistance value measured by the FSR 1300/1800.

At 2504, the logic may convert the resistance value to a digitized FSR input value.

At 2506, the logic may determine whether the digitized FSR input value meets or exceeds a threshold value that is to be met in order to register a FSR input event for the first control. If the threshold is not met at 2506, the process 2500 follows the “NO” route from block 2506 to block 2502 to await additional force data. If the threshold is met at 2506, the process 2500 follows the “YES” route from block 2506 to block 2508.

At 2508, the logic may determine whether an object (e.g., a finger, a thumb, etc.) is in contact with an adjacent, second control based at least in part on touch data provided by a touch sensor 2300 associated with a second control adjacent to the first control (e.g., thumb-operated control 114 or 115)—the touch data provided at a time at which the FSR resistance value is measured by the FSR 1300/1800. If the object is not in contact with the adjacent, second control, the process 2500 follows the “NO” route from block 2508 to block 2510, where the logic registers a FSR input event for the first control (e.g., by activating a binding for the first control). IF the object is in contact with the adjacent, second control, the process 2500 follows the “YES” route from block 2508 to block 2512.

At 2512, the logic may refrain from registering the FSR input event for the first control based at least in part on determining that the object is in contact with the second control. Thus, the process 2500 represents a sensor fusion algorithm that can be used to ignore spurious inputs at the FSR 1300/1800 based on a press of an adjacent control on the handheld controller.

FIG. 26 is a flow diagram of an example process 2600 for adjusting a FSR input threshold for a FSR 1300/1800 based on a hand size detected by an array of proximity sensors 800 in the handle 112/612 of the handheld controller 100/600.

At 2602, logic of a handheld controller 100/600 may determine, based at least in part on proximity data provided by an array of proximity sensors 800 that are spatially distributed on a handle of the controller 100/600, a size of a hand that is grasping the handle 112/612. The size of the hand may be determined from among a plurality of predefined hand sizes (e.g., small and large, or small, medium, and large, etc.).

At 2604, the logic may adjust, based at least in part on the size of the hand determined at block 2602, a threshold value to an adjusted threshold value that is to be met in order to register a FSR input event for the handle 112/612. This adjusted threshold value corresponds to a particular amount of force with which the handle 112/612 can be squeezed. For example, an amount of force corresponds to a measured resistance of the FSR 1300/1800 in the handle 112/612, and that resistance may correspond to a digitized FSR input value. When the user squeezes the handle, if the digitized FSR input value meets or exceeds the adjusted threshold value, a FSR input event can be registered. Thus, the threshold value may be adjusted to a lower value for a user with a smaller hand, while the threshold value may be adjusted to a greater value for a user with a larger hand, as detected by the array of proximity sensors 800 at block 2602. In some cases, a default threshold value may be configured for the controller 100/600 prior to detection of the hand size at block 2602, and the adjustment at block 2604 may be to increase or decrease the threshold value with respect to the default value.

As shown by the sub-blocks in FIG. 26, the process 2600 may involve more detailed operations. For example, the determining of the hand size at block 2602 may include sub-blocks 2606 and 2608.

At 2606, the logic may determine a number of proximity sensors of the array of proximity sensors 800 that provided the proximity data. For example, a small hand may only span a small subset of the proximity sensors in the array of proximity sensors 800, and the remaining proximity sensors that do not detect the small-sized hand may not provide the aforementioned proximity data. By contrast, a large hand may span the entirety of the array of proximity sensors 800, and, in this case, all (or at least a number above a threshold number) of the proximity sensors 800 may provide the proximity data.

At 2608, the logic may determine the size of the hand based at least in part on the number of proximity sensors (of the array 800) that provided the proximity data.

Additionally, as shown by sub-blocks 2610 and 2612, the adjustment of the threshold value at block 2604 may include adjusting the threshold value for one or more FSRs of the controller 100/600.

For example, at 2610, the logic may adjust a first threshold value (associated with a first FSR 1300(1)) that is to be met in order to register a FSR input event for the control 116. At 2612, the logic may, additionally or alternatively, adjust a second threshold value (associated with a second FSR 1300(2)) that is to be met in order to register a FSR input event for the handle 112/612.

FIG. 27 is a flow diagram of an example process 2700 for activing and deactivating a binding for a control of a handheld controller based on FSR input values. As shown by the off-page reference “A” in FIG. 27, the process 2700 may continue from any of the processes 2400, 2500, or 2600, but it does not have to.

At 2702, logic of a handheld controller 100/600 may determine, based at least in part on force data provided by a FSR 1300/1800 of the controller 100/600, at a first time, a first digitized FSR input value. This first digitized FSR input value may be converted from a first resistance value measured by the FSR 1300/1800 at the first time.

At 2704, the logic may determine whether the first digitized FSR input value meets or exceeds a threshold value that is to be met in order to register a FSR input event (e.g., for binding the control associated with the FSR 1300/1800). If the threshold is not met at 2704, the process 2700 follows the “NO” route from block 2704 to block 2702 where the logic awaits additional force data. If the threshold is met at 2704, the process 2700 follows the “YES” route from block 2704 to block 2706.

At 2706, the logic may register the FSR input event (e.g., to activate the binding associated with the control associated with the FSR 1300/1800) based at least in part on the first digitized FSR input value meeting or exceeding the threshold value.

At 2708, the logic may determine, based at least in part on force data provided by the FSR 1300/1800, at a second time after the first time, a second digitized FSR input value. This second digitized FSR input value may be converted from a second resistance value measured by the FSR 1300/1800 at the second time.

At 2710, the logic may determine whether the second digitized FSR input value is less than the first digitized FSR input value (i.e., whether the FSR input has decreased since a previous measurement by the FSR 1300/1800). If the second digitized FSR input value is less than the first digitized FSR input value, the process 2700 follows the “YES” route from block 2710 to block 2712, where the logic may deactivate the binding for the control associated with the FSR 1300/1800 (which can be thought of as unregistering a previously registered FSR input event that amounts to a press-and-hold input). If the second digitized FSR input value is not less than the first digitized FSR input value at block 2710, the process 2700 follows the “NO” route from block 2710 to block 2708 where the logic awaits additional force data from the FSR 1300/1800. The process 2700 may reflect the FSR detection mode illustrated in FIG. 21 and described above. Thus, the threshold evaluated at block 2704 may correspond to the baseline threshold value 2102 described with reference to FIG. 21.

FIG. 28 is a flow diagram of an example process 2800 for using a time-delay to determine whether to ignore FSR input for a first of multiple thresholds. As shown by the off-page reference “A” in FIG. 28, the process 2800 may continue from any of the processes 2400, 2500, or 2600, but it does not have to.

At 2802, logic of a handheld controller 100/600 may determine, based at least in part on force data provided by a FSR 1300/1800 of the controller 100/600, at a first time, a first digitized FSR input value. This first digitized FSR input value may be converted from a first resistance value measured by the FSR 1300/1800 at the first time.

At 2804, the logic may determine whether the first digitized FSR input value meets or exceeds a first threshold value (e.g., A1 2202 of FIG. 22) that is to be met in order to register a first FSR input event (e.g., for binding the control associated with the FSR 1300/1800). The first FSR input event may be associated with a first action (e.g., a first game mechanic). If the first threshold is not met at 2804, the process 2800 follows the “NO” route from block 2804 to block 2802 where the logic awaits additional force data. If the threshold is met at 2804, the process 2800 follows the “YES” route from block 2804 to block 2806.

At 2806, the logic may start monitoring a predefined time period (e.g., the time delay, t, in FIG. 22).

At 2808, the logic may determine, based at least in part on force data provided by the FSR 1300/1800, at a second time after the first time, a second digitized FSR input value. This second digitized FSR input value may be converted from a second resistance value measured by the FSR 1300/1800 at the second time.

At 2810, the logic may determine whether the second digitized FSR input value meets or exceeds a second threshold value (e.g., A2 2204 of FIG. 22) that is to be met in order to register a second FSR input event (e.g., for binding the control associated with the FSR 1300/1800). The second FSR input event may be associated with a second action (e.g., a second game mechanic) different from the first action, and the second threshold is greater than the first threshold. If the second threshold is not met at 2810, the process 2800 follows the “NO” route from block 2810 to block 2812 where the logic awaits determines whether the predefined time period has lapsed (e.g., whether the difference between the second time and the first time is less than the predefined time period). If the time period has not yet lapsed at block 2812, the process 2800 iterates by following the “NO” route from block 2812 back to block 2810. If the time period has lapsed at block 2812 and the second threshold has not been met, the process 2800 follows the “YES” route from block 2812 to block 2814 where the logic may register the first FSR input event for the first threshold (e.g., which may be associated with a first action or game mechanic).

If the second threshold is met at 2810, the process 2800 follows the “YES” route from block 2810 to block 2816, where the logic evaluates the predefined time period.). If the time period has not yet lapsed at block 2816, the process 2800 follows the “NO” route from block 2816 back to block 2818 where the logic refrains from registering the first FSR input event, and registers the second FSR input event associated with the second threshold (e.g., which may be associated with a second action or game mechanic). If the time period has lapsed at block 2816 and the second threshold has been met, the process 2800 follows the “YES” route from block 2816 to block 2820 where the logic may register both the first FSR input event for the first threshold and the second FSR input event for the second threshold. The process 2800 may reflect the FSR detection mode illustrated in FIG. 22 and described above.

FIG. 29 illustrates example components of a handheld controller, such as the controller 100 of FIG. 1, although the components shown in FIG. 29 can be implemented by the controller 600 as well. As illustrated, the handheld controller includes one or more input/output (I/O) devices 2902, such as the controls described above (e.g., joysticks, trackpads, triggers, etc.), potentially any other type of input or output devices. For example, the I/O devices 2902 may include one or more microphones to receive audio input, such as user voice input. In some implementations, one or more cameras or other types of sensors (e.g., inertial measurement unit (IMU)) may function as input devices to receive gestural input, such as motion of the handheld controller 100. In some embodiments, additional input devices may be provided in the form of a keyboard, keypad, mouse, touch screen, joystick, control buttons and the like. The input device(s) may further include control mechanisms, such as basic volume control button(s) for increasing/decreasing volume, as well as power and reset buttons.

The output devices, meanwhile, may include a display, a light element (e.g., LED), a vibrator to create haptic sensations, a speaker(s) (e.g., headphones), and/or the like. There may also be a simple light element (e.g., LED) to indicate a state such as, for example, when power is on. While a few examples have been provided, the handheld controller may additionally or alternatively comprise any other type of output device.

In addition, the handheld controller 100 may include one or more communication interfaces 2904 to facilitate a wireless connection to a network and/or to one or more remote systems (e.g., a host computing device executing an application, a game console, etc.). The communication interfaces 2904 may implement one or more of various wireless technologies, such as Wi-Fi, Bluetooth, radio frequency (RF), and so on. It is to be appreciated that the handheld controller 100 may further include physical ports to facilitate a wired connection to a network, a connected peripheral device, or a plug-in network device that communicates with other wireless networks.

In the illustrated implementation, the handheld controller further includes one or more processors 2906 and computer-readable media 2908. In some implementations, the processors(s) 2906 may include a central processing unit (CPU), a graphics processing unit (GPU), both CPU and GPU, a microprocessor, a digital signal processor or other processing units or components known in the art. Alternatively, or in addition, the functionally described herein can be performed, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip systems (SOCs), complex programmable logic devices (CPLDs), etc. Additionally, each of the processor(s) 2906 may possess its own local memory, which also may store program modules, program data, and/or one or more operating systems.

In general, the controller may include logic (e.g., software, hardware, and/or firmware, etc.) that is configured to implement the techniques, functionality, and/or operations described herein. The computer-readable media 2908 may include volatile and nonvolatile memory, removable and non-removable media implemented in any method or technology for storage of information, such as computer-readable instructions, data structures, program modules, or other data. Such memory includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, RAID storage systems, or any other medium which can be used to store the desired information and which can be accessed by a computing device. The computer-readable media 2908 may be implemented as computer-readable storage media (“CRSM”), which may be any available physical media accessible by the processor(s) 2906 to execute instructions stored on the computer-readable media 2908. In one basic implementation, CRSM may include random access memory (“RAM”) and Flash memory. In other implementations, CRSM may include, but is not limited to, read-only memory (“ROM”), electrically erasable programmable read-only memory (“EEPROM”), or any other tangible medium which can be used to store the desired information and which can be accessed by the processor(s) 2906.

Several modules such as instruction, datastores, and so forth may be stored within the computer-readable media 2908 and configured to execute on the processor(s) 2906. A few example functional modules are shown as stored in the computer-readable media 2908 and executed on the processor(s) 2906, although the same functionality may alternatively be implemented in hardware, firmware, or as a system on a chip (SOC).

An operating system module 2910 may be configured to manage hardware within and coupled to the handheld controller 100 for the benefit of other modules. In addition, the computer-readable media 2908 may store a network-communications module 2912 that enables the handheld controller 100 to communicate, via the communication interfaces 2904, with one or more other devices, such as a personal computing device executing an application (e.g., a game application), a game console, a HMD, a remote server, or the like. The computer-readable media 2908 may further include a game-session database 2914 to store data associated with a game (or other application) executing on the handheld controller or on a computing device to which the handheld controller 100 couples. The computer-readable media 2908 may also include a device-record database 2916 that stores data associated with devices to which the handheld controller 100 couples, such as the personal computing device, game console, HMD, remote server or the like. The computer-readable media 2908 may further store game-control instructions 2918 that configure the handheld controller 100 to function as a gaming controller, and universal-control instructions 2920 that configure the handheld controller 100 to function as a controller of other, non-gaming devices.

Unless otherwise indicated, all numbers expressing quantities used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. When further clarity is required, the term “about” has the meaning reasonably ascribed to it by a person skilled in the art when used in conjunction with a stated numerical value or range, i.e. denoting somewhat more or somewhat less than the stated value or range, to within a range of ±20% of the stated value; ±19% of the stated value; ±18% of the stated value; ±17% of the stated value; ±16% of the stated value; ±15% of the stated value; ±14% of the stated value; ±13% of the stated value; ±12% of the stated value; ±11% of the stated value; ±10% of the stated value; ±9% of the stated value; ±8% of the stated value; ±7% of the stated value; ±6% of the stated value; ±5% of the stated value; ±4% of the stated value; ±3% of the stated value; ±2% of the stated value; or ±1% of the stated value.

Although the subject matter has been described in language specific to structural features, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features described. Rather, the specific features are disclosed as illustrative forms of implementing the claims.

The disclosure is described with reference to specific exemplary embodiments herein, but those skilled in the art will recognize that the disclosure is not limited to those. It is contemplated that various features and aspects of the disclosure may be used individually or jointly and possibly in a different environment or application. For example, features shown with regards to a right-hand controller may be implemented also in a left-hand controller, and vice versa. The specification and drawings are, accordingly, to be regarded as illustrative and exemplary rather than restrictive. For example, the word “preferably,” and the phrase “preferably but not necessarily,” are used synonymously herein to consistently include the meaning of “not necessarily” or optionally. “Comprising,” “including,” and “having,” are intended to be open-ended terms. 

What is claimed is:
 1. A method of manufacturing a force sensing resistor (FSR), the method comprising: forming a first substrate made of polyimide and having a conductive material disposed on a front surface of the first substrate; providing one or more spacer layers atop the first substrate, leaving a portion of the conductive material uncovered by the one or more spacer layers; and providing a second substrate atop the first substrate such that the one or more spacer layers are interposed between the first substrate and the second substrate, the second substrate being flexible and having resistive material disposed on a back surface of the second substrate.
 2. The method of claim 1, wherein the conductive material comprises a metal layer.
 3. The method of claim 2, further comprising etching the metal layer to form interdigitated metal fingers on the front surface of the first substrate.
 4. The method of claim 3, wherein the metal layer comprises a copper clad layer, and wherein the interdigitated metal fingers comprise interdigitated copper fingers, the method further comprising depositing a layer of gold plating onto the interdigitated copper fingers to create gold-plated fingers.
 5. The method of claim 1, further comprising providing an actuator on the second substrate.
 6. The method of claim 1, wherein the providing the one or more spacer layers atop the first substrate comprises: depositing a coverlay of polyimide on the first substrate at a periphery of the first substrate, the coverlay covering a peripheral portion of the conductive material, wherein the portion of the conductive material comprises a remaining portion of the conductive material that is left uncovered by the coverlay; and depositing a layer of adhesive on the coverlay such that the remaining portion of the conductive material is left uncovered by the layer of adhesive, and such that a section of the coverlay is left uncovered by the layer of adhesive to create an air gap that allows air to ingress or egress from a space between the first substrate and the second substrate.
 7. The method of claim 1, further comprising, after providing the second substrate atop the first substrate: wrapping a portion of the first substrate around the second substrate such that the portion of the first substrate is disposed on a front surface of the second substrate; and attaching an actuator to the portion of the first substrate.
 8. The method of claim 1, wherein, when the FSR is operational, a resistance across output terminals of the FSR varies in response to variable force applied to the FSR.
 9. A method of manufacturing a force sensing resistor (FSR), the method comprising: forming a first substrate made of polyimide and having a conductive material disposed on a front surface of the first substrate; providing one or more spacer layers atop the first substrate at a periphery of the first substrate; and providing a second substrate atop the first substrate such that a portion of the second substrate is suspended over the first substrate by the one or more spacer layers, the second substrate being flexible and having resistive material disposed on a back surface of the second substrate.
 10. The method of claim 9, further comprising providing an actuator on the second substrate.
 11. The method of claim 10, wherein: an area of the conductive material that is left uncovered by the one or more spacer layers corresponds to an active area of the FSR; and the actuator is concentric with a center of the active area of the FSR.
 12. The method of claim 9, wherein the conductive material comprises a copper clad layer.
 13. The method of claim 12, further comprising: etching the copper clad layer to form interdigitated copper fingers on the front surface of the first substrate; and depositing a layer of gold plating onto the interdigitated copper fingers to create gold-plated fingers.
 14. The method of claim 13, wherein the providing the one or more spacer layers atop the first substrate comprises: depositing a coverlay of polyimide on the first substrate at the periphery of the first substrate, the coverlay covering a peripheral portion of the gold-plated fingers and leaving a remaining portion of the gold-plated fingers uncovered by the coverlay; and depositing a layer of adhesive on the coverlay such that the remaining portion of the gold-plated fingers is left uncovered by the layer of adhesive, and such that a section of the coverlay is left uncovered by the layer of adhesive to create an air gap that allows air to ingress or egress from a space between the first substrate and the second substrate.
 15. The method of claim 13, wherein the etching the copper clad layer comprises removing strips of copper material having a width of 0.2 millimeters (mm) to create a distance of 0.2 mm between pairs of adjacent copper fingers among the interdigitated copper fingers.
 16. A method of manufacturing a force sensing resistor (FSR), the method comprising: forming a first substrate made of polyimide and having a conductive material disposed on a front surface of the first substrate; and providing a second substrate atop the first substrate such that a center portion of the second substrate is suspended over the first substrate, the second substrate being flexible and having resistive material disposed on a back surface of the second substrate.
 17. The method of claim 16, wherein the conductive material comprises interdigitated metal fingers, the method further comprising coupling a first output terminal to a first set of the interdigitated metal fingers and a second output terminal to a second set of the interdigitated metal fingers, wherein, when the FSR is operational, a resistance across the first output terminal and the second output terminal varies in response to variable force applied to the FSR.
 18. The method of claim 16, further comprising, prior to the providing the second substrate atop the first substrate, providing one or more spacer layers atop the first substrate at a periphery of the first substrate.
 19. The method of claim 16, wherein the conductive material comprises a copper clad layer.
 20. The method of claim 19, further comprising: etching the copper clad layer to form interdigitated copper fingers on the front surface of the first substrate; and depositing a layer of gold plating onto the interdigitated copper fingers to create gold-plated fingers. 